<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
    <style>
        .detail {
            display: none;
        }

        .box {
            cursor: pointer;
        }

        .box:hover .detail {
            display: block;
        }
    </style>
</head>

<body>

    <div class="box">
        <span>购物车</span>
        <div class="detail">
            购物车的相关信息
        </div>
    </div>
</body>

</html>